Connection method of metal linear element and connection device of metal linear element

ABSTRACT

A connection method for connecting metal linear objects facing each other includes disposing a pair of rotators with a space interposed therebetween. Each rotator including a pair of holding portions that are provided with a space interposed therebetween and that are able to hold the metal linear objects. The connection method also includes holding the vicinities of end portions of the metal linear objects at the holding portions of the rotators to hang the metal linear objects therebetween so that the vicinities of the end portions of the metal linear objects are overlapped with each other in an axis direction and rotating the rotators relatively in the opposite directions around between the pair of holding portions as a rotation center. As a result, the metal linear objects are twisted with each other between the rotators to perform connection.

TECHNICAL FIELD

The present invention relates to a connection method for connectingmetal linear objects and a connection device.

BACKGROUND ART

For example, as a connection method for connecting steel cords, a methodhas bee disclosed in which after predetermined lengths of steel cordsare detwisted from the respective ends thereof, two cores are connectedto each other by a splice connection, and strands at the two sides areoverlapped around the peripheries of the cores and are twisted together,followed by covering the connection portion with a heat-shrinkable tube(for example, see Patent Document 1).

In addition, as a method for bonding ends of strand bundles A and B eachformed from a plurality of aligned strands, after the ends of theindividual strand bundles A and B are respectively divided into aplurality of groups A1, A2, - - - , and a plurality of groups B1,B2, - - - , A1 and B1, A2 and B2, - - - are overlapped and aligned toform overlapped portions X1, X2, - - - . Subsequently, after theindividual overlapped portions X1, X2, - - - are introduced inrespective tubular pathways, and two ends of each overlapped portion arerestrained, compressed air is supplied to each tubular pathway to obtaina bonding state of the overlapped portion by forming a twisted parttherein in which a central area thereof is in a non-twisted state, sothat strand portions are boned to each other (for example, see PatentDocument 2).

In this step, when the two ends of the overlapped portion (alignedportion) are held by fixtures or hands for restraint, the twisted partis formed in which the central area thereof is not twisted, and in whichright-side and left-side areas other than the central area are twistedin different directions (for example, the left-side part is S twisted,and the right-side part is Z twisted). That is, the twisted part isformed in which the central area thereof is in a non-twisted state.

Furthermore, There has been a method in which after end surfaces ofwires to be connected to each other are brought into contact, thecontact portion therebetween is irradiated with laser light to bemelted, and at least one wire is fed in the direction toward a meltingportion, so that a molten block larger than the outer diameter of eachwire is formed, and subsequently at least one wire is pulled back in thedirection opposite to the molten portion to adjust the shape thereof, sothat the connection is performed (for example, see Patent Document 3).

Patent Document 1: Japanese Unexamined Patent Application PublicationNo. 60-154833

Patent Document 2: Japanese Patent No. 2536803

Patent Document 3: Japanese Unexamined Patent Application PublicationNo. 8-19883

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

According to the method disclosed in the Patent Document 1, afterpredetermined lengths of the two cord ends to be connected together aredetwisted, and a particular connection is formed between the cores, thestrands at the two sides are overlapped around the periphery of theconnection portion and are twisted together by hand; hence, much laborand time are required. In addition, since the heat-shrinkable tube mustbe provided to cover the connection portion, it is difficult to performautomated production, the productivity cannot be improved, and as aresult, the cost is inevitably increased.

In addition, according to the method disclosed in the Patent Document 2,compressed air is supplied to the central area of the overlappedportion, and twisting at the right side and that at the left side areperformed in different directions; however, this method is only appliedto glass fibers and is not suitably used for connecting linear objectsmade of metal.

Furthermore, according to the method disclosed in the Patent Document 3,since being melted by irradiation of laser light, the individual wiresare connected to each other; however, the molten portion cannotwithstand a twisting operation performed in a subsequent step, andfracture may occur in some cases. Even if a product is obtained withoutgenerating fracture, when the product is used for reinforcing a rubberproduct such as a tire, it cannot withstand repeated tensile andflexural stresses, and as a result, fracture occurs. As described above,since the wire which is reinforced beforehand is processed by atempering treatment, the strength of the connection portion may bedegraded in some cases.

Accordingly, the present invention has been conceived in considerationof the above situations, and an object of the present invention is toprovide a connection method which can easily and tightly connect metallinear objects at a low cost and a connection device for connectingmetal linear objects.

Means for Solving the Problems

A connection method for connecting metal linear objects, according tothe present invention, which can solve the above problems, is aconnection method for connecting metal linear objects facing each other,which comprises the steps of: disposing a pair of rotators with a spaceinterposed therebetween, each rotator including a pair of holdingportions which are provided with a space interposed therebetween andwhich are able to hold the metal linear objects; holding the vicinitiesof end portions of the metal linear objects at the holding portions ofthe rotators to hang the metal linear objects therebetween so that thevicinities of the end portions of the metal linear objects areoverlapped with each other in an axis direction; and rotating therotators relatively in the opposite directions around between the pairof holding portions as a rotation center, whereby the metal linearobjects are twisted with each other between the rotators to performconnection.

According to the connection method for connecting metal linear objects,having the configuration described above, since the vicinities of theend portions of the metal linear objects are held by the holdingportions of the rotators and are hung therebetween so that thevicinities of the end portions of the metal linear objects areoverlapped with each other in the axis direction, and since the rotatorsare rotated relatively in the opposite directions around between theholding portions as the rotation center, the metal linear objects aretwisted together as if screwed between the rotators, and hence theconnection can be easily performed. In addition, the metal linearobjects uniformly twisted together are tightly connected by a frictionforce generated therebetween. In addition, since the connection can beperformed by simply rotating the rotators having the holding portions inthe opposite directions, a connection operation can be easily performedat a low cost.

Preferably, in the state in which the metal linear objects which arehung between the pair of rotators are restricted to move outside in thediameter direction, the rotators are rotated. Accordingly, the metallinear objects can be stably set along a twisting axis, and the metallinear objects can be uniformly and tightly twisted together while beingprevented from unstably moving and swinging.

A connection method for connecting metal linear objects, according tothe present invention, which can solve the above problems, is aconnection method for connecting metal linear objects facing each other,which comprises the steps of: disposing a pair of rotators with a spaceinterposed therebetween, each rotator including a pair of holdingportions which are provided with a space interposed therebetween andwhich are able to hold the metal linear objects; holding the vicinitiesof end portions of the metal linear objects, which are a main wire and abranch wire, at the holding portions of the rotators to hang the metallinear objects therebetween so that one metal linear object used as themain wire is disposed close to a rotation center side as compared to theother metal linear object used as the branch wire, and so that thevicinities of the end portions are overlapped with each other in an axisdirection; and in the state in which the metal linear objects which arehung between the pair of rotators are restricted to move outside in thediameter direction, rotating the rotators relatively in the oppositedirections around between the pair of holding portions as the rotationcenter, whereby the metal linear objects are twisted with each otherbetween the rotators to perform connection.

According to the connection method for connecting metal linear objects,having the configuration described above, since the vicinities of theend portions of the main wire and the branch wire are held by therespective holding portions to be hung therebetween so that thevicinities of the end portions of the main wire and the branch wire areoverlapped with each other in the axis direction, and since the rotatorsare rotated relatively in the opposite directions around between theholding portions as the rotation center, the branch wire is twisted asif screwed around the main wire, and hence the connection can be easilyperformed between the rotator. As a result, the twisted main wire andbranch wire are tightly connected together by a friction force generatedtherebetween. Since the connection can be performed by simply rotatingthe rotators having the holding portions in the opposite directions, aconnection operation can be easily performed at a low cost.

In addition, since the main wire and the branch wire are twistedtogether in the state in which the main wire and the branch wire whichare hung between the pair of rotators are restricted to move outside inthe diameter direction, the main wire and the branch wire can be stablyset along the twisting rotation axis and can be tightly twisted togetherwhile being prevented from unstably moving and swinging. In this step,compared to the branch wire, since the main wire is disposed close tothe rotation center side, the main wire and the branch wire are notuniformly nor equally overlapped, screwed, and twisted with each other,and the connection is performed such that the branch wire is woundaround the screwed main wire. As a result, the strength of theconnection portion can be suppressed from being degraded. That is, themain wire functioning as a central line can be responsible foranti-tensile load and the branch wire functioning as a lateral line(winding line) can be responsible for anti-sliding properties(anti-slipping properties).

Preferably, a tensile load ratio of the main wire to the branch wire isset in the range from 10:3 to 10:6. Accordingly, the connection can beperformed such that the branch wire is reliably and easily wound aroundthe screwed main wire.

Preferably, after the metal linear objects are twisted together, thetwisted portion is annealed at 250 to 500° C. for 10 seconds or more.Accordingly, a diameter shape forming rate of the connection portion canbe made approximately 100%, and the contact resistance of the connectionportion can be increased.

Preferably, as the holding portions of the rotators, slits are formed,each of which is opened at the outer circumference side of each rotatorand is extended to the vicinity of the rotation center thereof, and byinserting the metal linear objects in the slits, the metal linearobjects are held in the slits. Accordingly, by inserting the metallinear objects in the slits, the metal linear objects can be easily heldby the holding portions made of the slits. In addition, after the metallinear objects are connected to each other, the metal linear objects canbe easily removed from the slits.

Preferably, the rotators have the slits as one type of holding portionand, as the other type of holding portion, through-holes through whichthe metal linear objects are allowed to pass. As described above, sincethe other holding portions are formed of the through-holes, in the casein which the metal linear objects are held by passing through thethrough-holes, when the metal linear objects are twisted together, theouter circumferences of the metal linear objects are reliably held bythe inner circumferences of the through-holes, and hence the metallinear objects are further uniformly twisted together at the connectionportion.

Preferably, the metal linear objects comprise a material which generatesplastic deformation. Accordingly, the metal linear objects can betightly twisted together by generating the plastic deformation at theconnection portion, and hence a superior connection state can beobtained.

Preferably, at the connection portion formed by twisting the metallinear objects together, the metal linear objects are tightly fixed toeach other by a low-temperature melting soft metal. Accordingly,detwisting of the metal linear objects at the connection portion isprevented, and further, the strength of the connection portion can beimproved.

Preferably, the two end portions of the two linear objects are appliedwith tensile resistance during twisting so as to perform uniformscrewing. Accordingly, the twisting can be uniformly performed, and bythe twisting, the plastic deformation amount can be increased.

Preferably, when the metal linear objects are element wires, a pluralityof which is subsequently twisted together into a strand wire, thetwisting direction while the end portions are connected to each other isset to coincide with the twisting direction when a strand wire isformed. Accordingly, when element wires connected to each other aretwisted together to form a strand, since the twisting of metal linearobjects at each connection portion is further twisted, detwisting willnot occur, and hence the connection state by the twisting can bereliably maintained.

Preferably, when the metal linear objects are wires formed by twisting aplurality of element wires, the twisting direction while the endportions are connected to each other is set to coincide with thetwisting direction of the element wires. Accordingly, when the metallinear objects are connected to each other by twisting, since thetwisting between two strands is further twisted, detwisting between thestrands will not occur, and hence the twisting state at the connectionportion can be reliably maintained.

Preferably, after the metal linear objects are connected to each otherby twisting, at least one extra length portion of the end portions whichare not twisted together is removed by cutting. Accordingly, the metallinear objects can be placed in a connected state without leaving anunnecessary extra length portion.

Preferably, at least one of the end portions which are not twistedtogether is bent in the direction opposite to an introduction directionfor a subsequent step, and an extra length portion is cut off so as toleave a part thereof as a bent formation part. Accordingly, when themetal linear objects having the connection portion is introduced in asubsequent step as an intermediate product, a trouble can be reliablyprevented in which the cut end portion catches on something in a pathline for a subsequent step and is then cut off.

Preferably, after the twisting is performed, the connection portion isplastic-deformed by applying a compression force. Accordingly, theplastic deformation amount by the twisting can be maintained, andmeandering in the diameter direction can be suppressed.

In addition, a connection device for connecting metal linear objects,according to the present invention, which can solve the above problems,is a connection device for connecting metal linear objects facing eachother, which comprises: a pair of second rotators which are rotatablyprovided around the same axis center, each having a pair of holdingportions being capable of holding the metal linear objects and providedaround the axis center; a pair of first rotators engageable with teethformed along the peripheries of the second rotators; driven bevel gearsto be rotated with the respective first rotators; and a drive bevel gearengaged with the two driven bevel gears, wherein by rotation of thedrive bevel gear, the driven bevel gears are rotated in the oppositedirections, the rotations thereof are transmitted to the second rotatorsthrough the first rotators, and the second rotators are rotated in theopposite directions, whereby end portions of the metal linear objectsheld by the holding portions are twisted between the second rotators.

According to the connection device for connecting metal linear objects,having the above structure, since the vicinities of the end portions ofthe individual metal linear objects are held by the holding portions ofthe second rotators to be hung therebetween so that the vicinities ofthe end portions of the metal linear objects are overlapped in the axisdirection, and in the state described above, the drive bevel gear isrotated, the second rotators are rotated relatively in the oppositedirections through the driven bevel gears and the first rotators, andbetween the second rotators, the connection can be performed by twistingthe metal linear objects with each other. Furthermore, since a simplestructure is employed without using a particular mechanism or the like,the installation cost can be significantly reduced.

Preferably, since a linear object restriction member is further providedwhich restricts the metal linear objects, which are hung between thepair of second rotators, to move outside in the diameter direction, themetal linear objects are restricted to move outside in the diameterdirection when being twisted together and can be stably set along thetwisting axis, and as a result, while being prevented from meanderingand being decentered, the metal linear objects can be uniformly andtightly twisted together.

In addition, a connection device for connecting metal linear objects,according to the present invention, which can solve the above problems,is a connection device for connecting metal linear objects facing eachother, which comprises: a drive bevel gear to which a rotation force isapplied; a pair of driven bevel gears which are intersected with thedrive bevel gear and are applied with the rotation force; a pair ofdiscs integrally bonded to the respective driven bevel gears; and a pairof first rotators to be concentrically and integrally rotated with therespective discs. Furthermore, the connection device described abovefurther comprises: a pair of second rotators which are engaged with therespective first rotators, which are rotatably provided around the sameaxis center, and each of which have a pair of holding portions providedaround the axis center and being capable of holding the metal linearobject such that among the metal linear objects, a metal linear objectused as a main wire is disposed close to a rotation center side ascompared to a metal linear object used as a branch wire and such thatthe metal linear objects are hung so that the vicinities of end portionsthereof are overlapped with each other in the axis direction; and alinear object restriction member for restricting the metal linearobjects which are hung between the pair of second rotators to moveoutside in the diameter direction. In addition, by rotation of the drivebevel gear, the driven bevel gears are rotated in the oppositedirections, the rotations thereof are transmitted to the second rotatorsthrough the first rotators, and the second rotators are rotated in theopposite directions, whereby the end portions of the metal linearobjects are twisted together while being restricted by the linear objectrestriction member to move outside in the diameter direction between thesecond rotators.

According to the connection device for connecting metal linear objects,having the structure described above, the vicinities of the end portionsof the main wire and the branch wire are respectively held by theholding portions and are hung therebetween so as to be overlapped witheach other in the axis direction, and in the state described above, thedrive bevel gear is rotated. Accordingly, the second rotators arerotated relatively in the opposite directions through the driven bevelgears, the discs, and the first rotators, and between these secondrotators, the connection can be performed by twisting the branch wirearound the main wire. Furthermore, since a simple structure is employedwithout using a particular mechanism or the like, the installation costcan be significantly reduced.

In addition, since the linear object restriction member for restrictingthe main wire and the branch wire, which are hung between the pair ofsecond rotators, to move outside in the diameter direction is provided,when the main wire and the branch wire are twisted together, the mainwire and the branch wire are restricted to move outside in the diameterdirection and can be stably set along the twisting rotation axis, andhence while being prevented from meandering and being decentered, themain wire and the branch wire can be uniformly and tightly twistedtogether. In this step, since the main wire is disposed close to therotation center side as compared to the branch wire, the main wire andthe branch wire are not uniformly nor equally overlapped, screwed, andtwisted with each other, and as a result, connection is performed suchthat the branch wire is wound around the main wire. Accordingly, thestrength of the connection portion can be suppressed from beingdegraded. That is, the main wire 3 can be responsible for anti-tensileload as a central line, and the branch wire 4 can be responsible foranti-sliding properties as a lateral line.

Preferably, an electric heating means is further provided which heatsonly the connection portion after the end portions of the metal linearobjects are twisted together. Accordingly, after the connection isperformed, while the metal linear objects are set in the connectiondevice, steps including the annealing can be performed.

Preferably, as the holding portions, slits are formed, each of which isopened at the outer circumference side of each second rotator and isextended to the vicinity of the axial center described above, and byinserting the metal linear objects in the slits from the outercircumference sides of the above rotators, the metal linear objects areheld in the slits. Accordingly, by easily inserting the metal linearobjects in the slits, the metal linear object can be held by the holdingportions formed of the slits.

Preferably, the slits are each opened between teeth provided at theouter circumference side of each second rotator which are to be engagedwith those of the corresponding first rotator. As described above, sincethe slits, which are the holding portions for holding the metal linearobjects, are opened between teeth provided at the outer circumferencesides of the second rotators which are to be engaged with those of therespective first rotators, compared to the case in which the slit isformed at a position at which a tooth is present, the teeth of thesecond rotator can be reliably engaged with those of the correspondingfirst rotator. In addition, a decrease in tooth life and powertransmission defect from the first rotator can be suppressed.

Preferably, the first rotators are united with the respective drivenbevel gears. Accordingly, reduction in number of components andsimplification of the structure can be performed, and the cost can befurther reduced.

Preferably, the first rotators are concentrically united with therespective driven bevel gears with a space interposed therebetween.Accordingly, since the first rotators and the respective driven bevelgears are concentrically united together with a space interposedtherebetween, the length of the holding portion for twisting the branchwire around the main wire can be increased.

Preferably, the second rotators are engaged with pairs of idle rotatorslocated at the side opposite to the first rotators, and by the idlerotators, the second rotators are supported at the side opposite to thefirst rotators. Accordingly, together with the first rotators, thesecond rotators can be rotatably and detachably supported by the idlerotators without using bearings or the like.

Preferably, between the second rotators, a spacer having a predeterminedlength dimension is provided. Accordingly, the metal linear objects canbe twisted together by a predetermined length, and in addition, thetwisting can be more uniformly performed.

Preferably, the spacer is the linear object restriction member. Asdescribed above, when the linear object restriction member and thespacer are formed as one member, the number of components can bereduced, and the structure of the device can be simplified.

Preferably, the number of teeth of each first rotator is smaller thanthe number of teeth of each driven bevel gear. Accordingly, since arotation force is transmitted from the first rotator having a smallernumber of teeth than that of the driven bevel gear to the correspondingsecond rotator, by increasing the transmission torque, the twistingtorque can be increased.

Advantages

According to the present invention, since the vicinities of the endportions of the metal linear objects are held by the holding portions ofthe rotators to be hung therebetween so that the vicinities of the endportions of the metal linear objects are overlapped with each other inthe axis direction, and since the rotators are rotated relatively in theopposite directions around between the holding portions of the rotatorsas a rotation center, the metal linear objects are uniformly twistedtogether as if being screwed, thereby easily performing the connection.In addition, the metal linear objects which are uniformly twistedtogether are tightly connected to each other by a friction forcegenerated therebetween. In addition, since the connection can beperformed by simply rotating the rotators having the holding portions inthe opposite directions, a connection operation can be easily performedat a low cost. Furthermore, since the diameter shape forming rate of thetwisted portion can be made approximately 100% by annealing, theconnection can be more tightly performed by a friction force generatedtherebetween.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 includes side views each showing metal linear objects accordingto a first embodiment of the present invention.

FIG. 2 includes side views each showing the state in which a connectionportion in FIG. 1 is tightly fixed with a low-temperature melting softmetal.

FIG. 3 is a front view of a connection device connecting the metallinear objects shown in FIG. 1.

FIG. 4 is a cross-sectional view of the connection device shown in FIG.3.

FIG. 5 includes side views each showing metal linear objects accordingto a second embodiment of the present invention.

FIG. 6 is a front view of a connection device connecting the metallinear objects shown in FIG. 5.

FIG. 7 is a cross-sectional view of the connection device shown in FIG.6.

FIG. 8 is a cross-sectional view showing the structure of a coreaccording to an example.

FIG. 9 is a cross-sectional view showing the structure of a sheathaccording to the example.

FIG. 10 is a cross-sectional view showing the structure of a metal cordaccording to the example.

REFERENCE NUMERALS

1 metal linear object

3 main wire (metal linear object)

4 branch wire (metal linear object)

7 connection portion

8 low-temperature melting soft metal

10 metal linear object

11 connection device

12 low-temperature melting soft metal

31 a, 31 b idle gear (idle rotator)

41 a, 41 b second spur gear (rotator, second rotator)

43 through-hole (holding portion)

44 slit (holding portion)

45 spacer (linear object restriction member)

51 a, 51 b transmission gear (spur gear, bevel gear)

54 first spur gear (first rotator)

55 driven bevel gear

56 drive bevel gear

60 connection device

62 drive bevel gear

63, 64 driven bevel gear

65, 66 disc

67, 68 first spur gear (first rotator)

69, 70 second spur gear (rotator, second rotator)

71, 72 idle gear (idle rotator)

86 through-hole (holding portion)

87 slit (holding portion)

92 spacer (linear object restriction member)

BEST MODES FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings. Inaddition, in this description, the same element or an element having thesame function is designated by the same reference numeral, anddescription thereof will not be repeated.

With reference to FIGS. 1 to 4, a preferable first embodiment of thepresent invention will be described.

As shown in FIG. 1( a), end portions 1 a of metal linear objects 1 areconnected to each other at a connection portion 2. At this connectionportion 2, the metal linear objects 1 are twisted equivalently with eachother, and at this twisted portion, the metal linear objects 1 areplastic-deformed and united together. The metal linear objects 1 whichare twisted equivalently with each other are strongly connected by afriction force generated therebetween by twisting.

In addition, as shown in FIG. 1( b), in the case in which after a bentportion 1 b is formed by bending the end portion 1 a of the metal linearobject 1, located at an introduction direction side of the connectionportion 2, in the direction opposite to the introduction direction, anextra length portion is removed by cutting to leave a part of the endportion 1 a having a length of 3 to 10 mm used as a bent formation part,and this metal linear object 1 is introduced as an intermediate productto a path line for a subsequent step (in the direction shown by thearrow in the figure), a trouble can be reliably prevented in which theconnection portion 2 is cut off when the cut end portion 1 a catches onsomething and generates an excessive load to be applied thereto.

In addition, when the two metal linear objects 1 are twisted together,by applying tensile resistance to each terminal portion, more uniformtwisting can be performed.

This metal linear object 1 is formed, for example, of a plasticdeformable material, such as steel, copper, or aluminum. Hence, thetwisted shape is maintained, and even when a tensile force or the likeis applied to the metal linear object 1, the connection state can befirmly maintained.

In addition, when the connection portion 2 formed by connecting themetal linear objects 1 to each other by the above method is compressedby a vise or the like using a fixture formed of two half parts having adiameter equal to or slightly smaller than that of the connectionportion, tighter connection can be performed.

In addition, as the metal linear object 1, various types of linearobjects, such as a single element wire, a twisted wire (strand), amultiple twisted strand (cord) which is formed by twisting twistedwires, may be used.

In addition, as shown in FIG. 2, the metal linear objects 1 arepreferably tightly fixed to each other at the connection portion 2 awith a low-temperature melting soft metal 12. As the low-temperaturemelting soft metal, for example, a copper-tin alloy (solder) may bepreferably used. In the structure shown in FIG. 2( a), thelow-temperature melting soft metal 12 is brazed using its wettabilityalong each boundary portion between the twisted metal linear objects 1,and the metal linear objects 1 are tightly fixed to each other; however,the entire connection portion 2 may be overlaid with the low-temperaturemelting soft metal 12 for tight fixing.

In addition, as shown in FIG. 2( b), when the bent portion 1 b is formedby bending the end portion 1 a of the metal linear object 1, located atan introduction direction side of the connection portion 2, in thedirection opposite to the introduction direction, the trouble in which,for example, the connection portion 2 is cut off can be reliablyprevented as described above.

As described above, since the metal linear objects 1 are tightly fixedto each other with the low-temperature melting soft metal 12, detwistingof the metal linear objects 1 at the connection portion 2 a can beprevented, and in addition, the strength of the connection portion 2 canbe improved. In addition, as a fixing agent to be provided between themetal linear objects 1, instead of the low-temperature melting softmetal 12, an adhesive may also be used.

Next, a connection device used for connecting the metal linear objects 1will be described. FIG. 3 is a front view of a connection deviceconnecting metal linear objects, and FIG. 4 is a cross-sectional view ofthe connection device connecting metal linear objects.

As shown in FIGS. 3 and 4, this connection device 11 includes a casing21 in the form of a box. This casing 21 is formed of a lower casing 22and an upper casing 23 provided above this lower casing 22, and theupper casing 23 is turnably connected to the lower casing 22 with ahinge 24.

In the lower casing 22, a pair of idle gears 31 a is provided at oneside plate 22 a with a space interposed therebetween, and shafts 32 a ofthose idle gears 31 a are rotatably supported at the side plate 22 a bybearings 33 a.

In addition, also at the other side plate 22 b of the lower casing 22, apair of idle gears 31 b is provided with a space interposedtherebetween, and shafts 32 b of those idle gears 31 b are rotatablysupported at the side plate 22 b by bearings 33 b.

In addition, the idle gears 31 a at the side plate 22 a are disposed soas to face the respective idle gears 31 b at the side plate 22 b.

Second spur gears 41 a and 41 b, which are second rotators each formedof a spur gear having gear teeth (not shown) formed along the peripherythereof, are disposed to be engaged with the idle gears 31 a and 31 b.In addition, when these second spur gears 41 a and 41 b are engaged withthe idle gears 31 a and 31 b, the spur gears 41 a and 41 b are rotatablysupported in the lower casing 22.

In each of these second spur gears 41 a and 41 b, at an eccentricposition in the vicinity of the center thereof, a through-hole 43 havinga diameter slightly larger than that of the metal linear object 1 isformed, and this through-hole 43 is designed to allow the metal linearobject 1 to pass therethrough. In addition, in these second spur gears41 a and 41 b, slits 44 which are opened between teeth provided at theouter circumferences thereof are formed to extend to the centers of thesecond spur gears 41 a and 41 b, and the bottoms of these slits 44 aredisposed at the central positions of the second spur gears 41 a and 41b. These slits 44 each have a width dimension slightly larger than thediameter of the metal linear object 1 and are designed so that the metallinear objects 1 can be inserted therein from the respective openportions provided at the outer circumference sides of the second spurgears 41 a and 41 b. In addition, the formation direction of each slit44 is angled in the vicinity of the bottom portion of the slit 44, sothat the metal linear object 1 disposed in the vicinity of the bottomportion is not likely to move to the outside in the diameter directionof each of the second spur gears 41 a and 41 b. That is, the metallinear object 1 can be easily held at the bottom portion.

Between the second spur gears 41 a and 41 b, a hollow cylindrical spacer45 is disposed at the central positions thereof. The spacer 45 has anotch portion 46 at a part of the periphery thereof along the axisdirection. The second spur gears 41 a and 41 b have protrusions 47 a and47 b facing each other at the central positions thereof, and theseprotrusions 47 a and 47 b are designed to be fitted in the spacer 45. Inaddition, by this spacer 45, the second spur gears 41 a and 41 bprovided in the lower casing 22 are disposed with a predetermined spaceinterposed therebetween.

In addition, the inside diameter of the spacer 45 is formed to beslightly larger than the state in which two metal linear objects 1 areoverlapped in the axis direction, and the spacer 45 is designed tofunction as a linear object restriction member for restricting the metallinear objects 1 which are hung between the pair of the second spurgears 41 a and 41 b to move outside in the diameter direction. As oneexample, the inside diameter of the spacer 45 is 2.2 times the outsidediameter of the metal linear object 1.

In addition, in the lower casing 22, concave portions 48 a and 48 b areformed along the upper edges of the side plates 22 a and 22 b, and thecentral portions of the second spur gears 41 a and 41 b and theirvicinities in the lower casing 22 are exposed.

In the upper casing 23, at one side plate 23 a and the other side plate23 b, transmission gears 51 a and 51 b are respectively provided atpositions facing each other, and these transmission gears 51 a and 51 bare formed so that shafts 52 a and 52 b thereof are rotatably supportedat the side plates 23 a and 23 b by bearings 53 a and 53 b,respectively.

These transmission gears 51 a and 51 b each have a first spur gear 54and a driven bevel gear 55, and the first spur gears 54 are designed tobe engaged with the second spur gears 41 a and 41 b.

In addition, at a roof plate 23 c of the upper casing 23, a drive bevelgear 56 is provided, and this drive bevel gear 56 is engaged with thedriven bevel gears 55 of the transmission gears 51 a and 51 b. In thisdrive bevel gear 56, a shaft 57 thereof is rotatably supported by abearing 59 provided at the roof plate 23 c, and at an end portion of theshaft 57 projecting to the upper surface side of the roof plate 23 c,which is opposite to the drive bevel gear 56, a handle 58 is provided.In addition, by holding and rotating this handle 58, the drive bevelgear 56 is rotated. In this embodiment, the driven bevel gears 55 andthe drive bevel gear 56 are spiral bevel gears.

As one example, the number of teeth of the drive bevel gear 56 is 20,the numbers of teeth of the bevel gear 55 and the first spur gear 54 ofeach of the transmission gears 51 a and 51 b are each 40, the numbers ofteeth of the second spur gears 41 a and 41 b are each 24, and thenumbers of teeth of the idle gears 31 a and 31 b are each 12. In thiscase, when the drive bevel gear 56 rotates twice, the transmission gears51 a and 51 b rotate once. In addition, when the transmission gears 51 aand 51 b rotate 3 times, the second spur gears 41 a and 41 b rotate 5times.

Next, a method for connecting the metal linear objects 1 using the aboveconnection device 11 will be described.

First, from the two sides of the connection device 11, the end portions1 a of the metal linear objects 1 are inserted in the respective slits44 of the second spur gears 41 a and 41 b in the casing 21 and areextended outside by a predetermined length through the through-holes 43of the second spur gears 41 a and 41 b located at the opposite sides.

Alternatively, after the second spur gears 41 a and 41 b are removedfrom the casing 21 of the connection device 11, the metal linear objects1 are inserted in the gears, and the gears are again disposed at thepredetermined positions in the casing 21.

In the state described above, the handle 58 of the connection device 11is held and rotated. Accordingly, the drive bevel gear 56 is rotated,and by this rotation, the transmission gears 51 a and 51 b are rotatedin the opposite directions. Furthermore, the rotations of thetransmission gears 51 a and 51 b are transmitted to the second spurgears 41 a and 41 b, and these second spur gears 41 a and 41 b arerotated in the opposite directions.

Accordingly, the metal linear objects 1 which are restricted by passingthrough the through-holes 43 and the slits 44 of the second spur gears41 a and 41 b are twisted therebetween. In this step, the metal linearobjects 1 are pulled toward the connection portion 2 by twisting, and aforce reducing the distance between the second spur gears 41 a and 41 bis generated; however, since the spacer 45 is disposed therebetween, thesecond spur gears 41 a and 41 b are maintained at the predeterminedpositions, and hence uniform twisting can be performed.

In addition, since the spacer 45 is disposed at the position in thevicinity of the outside of the metal linear objects 1, which are hungbetween the second spur gears 41 a and 41 b, in the diameter direction,when twisting is performed, the metal linear objects 1 are restricted tomove outside in the diameter direction. That is, even when the metallinear objects 1 tend to meander (or be decentered) during twisting, themetal linear objects 1 are brought into contact with the innercircumference surface of the spacer 45, and by this contact resistance,the metal linear objects 1 are stably set along the twisting axis (alongthe rotation shafts of the second spur gears 41 a and 41 b).Accordingly, the metal linear objects 1 can be uniformly and tightlytwisted with each other. In addition, after the twisting is performedpredetermined times, the handle 58 is stopped so as to stop thetwisting.

Next, as shown in FIG. 4, in the state in which the connection portion 2is formed by twisting the metal linear objects 1 together, terminals h1and h2 of a heating device H used as an electric heating means providedin the connection device 11 are connected to the end portions 1 a of themetal linear objects 1. Subsequently, by tuning on the switch of theheating device H, electricity is supplied between the terminals h1 andh2, and by the electrical resistance of the connection portion 2 itself,the twisted portion is heated to 250 to 500° C. and preferablyapproximately 400° C. and is maintained for at least 10 seconds or moreand preferably approximately 20 seconds for annealing. As a result, adiameter performing percentage of the connection portion 2 can be madeapproximately 100%.

Next, by turning the upper casing 23 using the hinge 24, the upperportion of the lower casing 22 is opened, and the second spur gears 41 aand 41 b in the lower casing 22 are brought out.

The second spur gears 41 a and 41 b are moved in the directions so as tobe apart from each other, and the end portions 1 a of the metal linearobjects 1 are pulled out from the through-holes 43 of the second spurgears 41 a and 41 b. In addition, the metal linear objects 1 are furtherpulled out from the slits 44 of the second spur gears 41 a and 41 b, andthe spacer 45 is removed by pulling out the metal linear objects 1 fromthe notch portion 46 thereof.

Subsequently, non-twisted portions of the end portions 1 a extended fromthe connection portion 2 are cut off by a nipper, a clipper, or thelike.

As a result, the metal linear objects 1 are uniformly twisted togetherat the end portions 1 a thereof and are united together by plasticdeformation of the twisted connection portion 2, so that a tightlyconnected state can be obtained.

In addition, without performing annealing after twisting, the connectionportion 2 a can be tightly fixed with the low-temperature melting softmetal 12, as shown in FIG. 2. Accordingly, detwisting of the connectionportion 2 a can be prevented, and in addition, a tightly connected statecan be obtained.

As described above, according to this embodiment, the vicinities of theend portions 1 a of the metal linear objects 1 are held by holdingportions formed of the through-holes 43 and the slits 44 of the secondspur gears 41 a and 41 b and are hung therebetween so as to beoverlapped with each other in the axis direction, and the second spurgears 41 a and 41 b are rotated relatively in the opposite directions.As a result, between the second spur gears 41 a and 41 b, the metallinear objects 1 can be easily and uniformly twisted together andplastic-deformed at a low cost, so that tight connection can beperformed.

In addition, since the through-holes 43 and the slits 44 of the secondspur gears 41 a and 41 b are used as the holding portions for the metallinear objects 1, by inserting the metal linear objects 1 in the slits44, the metal linear objects 1 can be easily held by the holdingportions formed of the slits 44. In addition, when the metal linearobjects 1 are held by being inserted in the through-holes 43, the outercircumferences of the metal linear objects 1 can be reliably held by theinner circumferences of the through-holes 43 while the metal linearobjects 1 are twisted together, and uniform twisting can be furtherperformed.

In addition, the spacer 45 functions as the linear object restrictionmember, and in the state in which the metal linear objects 1, which arehung between a pair of rotators, are restricted to move outside in thediameter direction, the metal linear objects 1 are twisted together.Hence, the metal linear objects 1 can be stably set along the twistingaxis, and while being prevented from unstably moving and swinging, themetal linear objects 1 can be uniformly and tightly twisted together.

In addition, by supplying electricity using the heating device H betweenthe end portions 1 a at the connection portion 2 formed by twisting themetal linear objects 1 together, the connection portion 2 placed in theconnection device is heated to a temperature of 250 to 500° C. and ismaintained for 10 seconds or more for annealing. As a result, thediameter shape forming rate of the connection portion 2 is madeapproximately 100% by the simple heating device, so that the contactresistance of the connection portion can be improved.

In addition, since the connection device 11 connecting the metal linearobjects 1 together has a simple structure which uses no particularmechanism or the like, the installation cost can be significantlyreduced. Furthermore, since the linear object restriction member and thespacer 45 are formed as one member, the number of components can bereduced, and the device structure can be simplified. In addition, thespacer 45 and the linear object restriction member may be separatelyprovided.

In particular, since the slits 44 used as the holding portions forholding the metal linear objects 1 are opened between teeth provided atthe outer circumference sides of the second spur gears 41 a and 41 bwhich are to be engaged with those of the first spur gears 54 of thetransmission gears 51 a and 51 b, compared to the case in which theslits are formed at the tooth positions, the teeth of the second spurgears 41 a and 41 b can be reliably engaged with those of the first spurgears 54. In addition, a decrease in tooth life and a transmissiondefect of power from the transmission gears 51 a and 51 b can besuppressed.

Since the transmission gears 51 a and 51 b each having the first spurgear 54 and the driven bevel gear 55, which are united together, areused, the reduction in number of components and simplification of thestructure can be performed, and furthermore, cost reduction can also beachieved.

In addition, since the pairs of idle gears 31 a and 31 b are provided atthe sides opposite to the transmission gears 51 a and 51 b and areengaged with the second spur gears 41 a and 41 b so as to rotatablysupport the second spur gears 41 a and 41 b, by the idle gears 31 a and31 b together with the transmission gears 51 a and 51 b, the second spurgears 41 a and 41 b can be rotatably and detachably supported withoutusing bearings or the like.

In addition, since the spacer 45 having a predetermined length isprovided between the second spur gears 41 a and 41 b, the metal linearobjects 1 can be twisted by a predetermined length for connection, andin addition, the twisting can be further uniformly performed.

In addition, since the metal linear objects 1 are tightly fixed togetherby the low-temperature melting soft metal 12 at the connection portion2, detwisting of the metal linear objects 1 can be suppressed, andfurther the contact resistance of the connection portion 2 can beimproved.

In this embodiment, although the case in which the metal linear objects1 each formed of a single wire are connected to each other has beendescribed by way of example, as the metal linear objects 1 to beconnected to each other, twisted wires each formed by twisting aplurality of element wires may also be used. In the case describedabove, the twisting direction when the end portions 1 a are connected toeach other is preferably set to coincide with the twisting direction ofthe element wires. Accordingly, when the metal linear objects 1 aretwisted with each other for connection, twisting of two twisted wires isfurther performed, and hence the connection condition by the twistingcan be reliably maintained.

In addition, in the case in which a plurality of metal linear objects 1which are twisted beforehand for connection are twisted to form atwisted wire, the twisting direction when the end portions 1 a areconnected to each other is preferably set to coincide with the twistingdirection when the twisted wire is formed. Accordingly, when a pluralityof the metal linear objects 1 are twisted together, the state of theconnection portion 2 of the metal linear objects 1 can be reliablymaintained.

In addition, as the above connection method, although the case in whichthe end portions 1 a of a pair of the metal linear objects 1 areconnected to each other has been described by way of example, even whenthe metal linear object 1 has a circular shape, of course, the abovemethod can also be applied to connect two end portions 1 a of the metallinear object 1.

In addition, in a circular metal cord formed by twisting the metallinear objects 1 while they are being circularly warped, when endportions of one metal linear object 1 are connected to each other, metallinear objects 1 not to be connected, which are other than the metallinear object 1 to be connected, are hooked by a plurality of pins, andthese pins are moved to the direction so as to be apart from the metallinear object 1 to be connected. Accordingly, the connection ispreferably performed in the state in which the metal linear object 1 tobe connected is placed apart from the metal linear objects 1 not to beconnected.

Next, with reference to FIGS. 5 to 7, a preferable second embodiment ofthe present invention will be described.

As shown in FIG. 5( a), in a metal linear object 10, a main wire 3,which is a base wire screwed by a small twist having a long wavelengthcycle, and a branch wire 4, which is a winding wire twisted with themain wire 3 by a large twist having a shorter wavelength cycle than thatof the main wire 3, are connected to each other at end portions 5 and 6thereof at a connection portion 7. At this connection portion 7, whilethe main wire 3 and the branch wire 4 are twisted together, the twistingis performed such that the branch wire 4 is wound around the main wire3. At the twisted portion, the main wire 3 and the branch wire 4 aremutually plastic-deformed and are tightly connected together by afriction force generated therebetween.

In addition, as shown in FIG. 5( b), in the case in which after a bentportion 5 a is formed by bending the end portion 5 of the metal linearobject 10, located at an introduction direction side of the connectionportion 7, in the direction opposite to the introduction direction side,an extra length portion is removed by cutting to leave a part of the endportion 5 having a length of 3 to 10 mm used as a bent formation part,and this metal linear object 10 is introduced as an intermediate productto a path line for a subsequent step (in the direction shown by thearrow in the figure), a trouble can be reliably prevented in which theconnection portion 7 is cut off when the cut end portion 5 catches onsomething and generates an excessive load to be applied thereto.

The main wire 3 is formed, for example, of a plastic deformablematerial, such as steel, copper, or aluminum. In addition, as the caseof the main wire 3, the branch wire 4 is also formed by using a plasticdeformable material, such as steel, copper, or aluminum. Hence, atwisted shape of the main wire 3 and the branch wire 4 is maintained,and even when a tensile force or the like is applied to the metal linearobject 10, the connection state can be firmly maintained. In addition,as the metal linear object 10, various typed of linear objects, such asa single element wire, a twisted wire (strand), and a multiple twistedstrand (cord) formed by twisting twisted wires together, may be used.

In addition, in the metal linear object 10, the main wire 3 and thebranch wire 4 are tightly fixed together at the connection portion 7 bya low-temperature melting soft metal 8. As the low-temperature meltingsoft metal 8, for example, a copper-tin alloy (solder) may be preferablyused. In FIG. 5, the individual boundary portions between the twistedmain wire 3 and branch wire 4 are brazed with the low-temperaturemelting soft metal 8 using the wettability thereof, so that the mainwire 3 and the branch wire 4 are tightly fixed together; however, theentire connection portion 7 may be overlaid with the low-temperaturemelting soft metal 8 for tight fixing.

As described above, since the main wire 3 and the branch wire 4 aretightly fixed to each other with the low-temperature melting soft metal8, detwisting of the main wire 3 and the branch wire 4 at the connectionportion 7 can be suppressed, and in addition, the contact resistance ofthe connection portion 7 can be improved. In addition, as a fixing agentfor the main wire 3 and the branch wire 4, instead of thelow-temperature melting soft metal 8, an adhesive may also be used.

Next, with reference to FIGS. 6 and 7, a connection device used forconnecting the metal linear object 10 will be described.

As shown in FIGS. 6 and 7, this connection device 60 primarily includesa casing 61, a drive bevel gear 62, a pair of driven bevel gears 63 and64, a pair of discs 65 and 66, first spur gears 67 and 68 which are apair of first rotators, second spur gears 69 and 70 which are a pair ofsecond rotators having a small diameter, and two pairs of idle gears 71and 72 which are idle rotators. In addition, in this embodiment, thedrive bevel gear 62 and the driven bevel gears 63 and 64 are straightbevel gears.

The casing 61 is formed of a lower casing 73 and an upper casing 74provided above the lower casing 73, and the lower casing 73 and theupper casing 74 are turnably connected to each other with a hinge 75. Inthe lower casing 73, the second spur gears 69 and 70 and the idle gears71 and 72 are received, and in the upper casing 74, the drive bevel gear62, the driven bevel gears 63 and 64, and the discs 65 and 66, and thefirst spur gears 67 and 68 are received.

In the drive bevel gear 62, a shaft 76 is rotatably supported at a roofplate 78 of the upper casing 74 through a bearing 77. The drive bevelgear 62 is rotated by rotating a handle 79 provided at an end portion ofthe shaft 76. The number of teeth of the drive bevel gear 62 is, forexample, 20 (20T). The drive bevel gear 62 is engaged with the drivenbevel gears 63 and 64.

The driven bevel gears 63 and 64 have shafts 80 and 81, respectively,perpendicular to the shaft 76 of the drive bevel gear 62, the shaft 80of these shafts is rotatably supported at a side plate 83 of the uppercasing 74 through a bearing 82, and the other shaft 81 is rotatablysupported at the other side plate 85 of the upper casing 74 through abearing 84. The number of teeth of each of the driven bevel gears 63 and64 is, for example, 40 (40T).

The discs 65 and 66 are integrally and concentrically bonded to thedriven bevel gears 63 and 64, respectively, and each have apredetermined thickness dimension T1 and approximately the same diameteras that of each of the driven bevel gears 63 and 64. In addition, afterbeing separately formed, the discs 65 and 66 may be tightly fixed to thedriven bevel gears 63 and 64, respectively.

The first spur gears 67 and 68 are integrally and concentricallyconnected to the discs 65 and 66, respectively. Since the first spurgears 67 and 68 are disposed outside the driven bevel gears 63 and 64with the discs 65 and 66 having a thickness dimension T1 interposedtherebetween, a relatively large space dimension L1 is formed betweenthe first spur gears 67 and 68. The numbers of the first spur gears 67and 68 are each, for example, 32 (32T).

The second spur gears 69 and 70 are disposed with the space dimension L1which is formed between the first spur gears 67 and 68 and are engagedwith the first spur gears 67 and 68, respectively.

At an eccentric position in the vicinity of the center of each of thesecond spur gears 69 and 70, a through-hole 86 having a diameterslightly larger than that of the branch wire 4 is formed as one type ofholding portion, and this through-hole 86 is designed to allow thebranch wire 4 to pass therethrough.

In addition, in each of the second spur gears 69 and 70, a slit 87 usedas the other type of holding portion, which is opened between teethprovided at the outer circumference of each of the above gears, isformed by cutting from a position located slightly outside the rotationcenter, the position being used as a bottom portion of the slit. Theslit 87 has a width dimension slightly larger than the diameter of themain wire 3 and is designed so that the main wire 3 can be insertedtherein from the open portion provided at the outer circumference side.In addition, although this slit 87 is formed so that a part thereof inthe vicinity of the bottom portion is slightly angled, this angleddirection is changed in accordance with the twisting direction whenconnection is performed and is formed so that the main wire 3 insertedin the vicinity of the bottom portion is not likely to be displacedoutside in the diameter direction. That is, it is designed so that themain wire 3 is easily held at the bottom portion of the slit 87. In thiscase, the eccentric amount of the center of the bottom portion of theslit 87 from the rotation center of the second spur gears 69 and 70 issmaller than the eccentric amount of the center of the through-hole 86from the rotation center of the second spur gears 69 and 70.

The through-holes 86, the slits 87, and the vicinities thereof of thesecond spur gears 69 and 70 are exposed through concave portions 90 and91 formed along the upper edges of two side plates 88 and 89 of thelower casing 73.

In addition, between the second spur gears 69 and 70, a hollowcylindrical spacer 92 used as one holding portion is formed within thespace dimension L1 so that the rotation center thereof is coaxial withthe second spur gears 69 and 70. This spacer 92 has a notch portion 93formed in part of the periphery thereof along the axis direction.

The second spur gears 69 and 70 have protrusions 94 and 95 facing eachother at the rotation central positions thereof, and these protrusions94 and 95 are fitted in the spacer 92. In addition, by this spacer 92,the second spur gears 69 and 70 are disposed at predetermined positionswith the space dimension L1 interposed therebetween.

In addition, since the inside diameter of the spacer 92 is formed to beslightly larger than the dimension obtained when the main wire 3 and thebranch wire 4 are bundled together, the spacer 92 functions as a linearobject restriction member for restricting the main wire 3 and the branchwire 4 which are hung between the pair of the second spur gears 69 and70 to move outside in the diameter direction. The inside diameter of thespacer 92 is, for example, 2.2 times the outside diameter of the mainwire 3 or the branch wire 4.

In the idle gears 71 and 72, a pair of shafts 96 and a pair of shafts 97are rotatably supported at the two side plates 88 and 89 of the lowercasing 73 through bearings 98 and 99, respectively, and a pair of theidle gears 71 and a pair of the idle gears 72, each pair being providedwith a space interposed therebetween, are engaged with the second spurgears 69 [[71]] and 70 [[72]], respectively. Since the idle gears 71 and72 each have a number of teeth, for example, of 12 (12T) and aredisposed in the lower casing 73, the idle gears 71 and 72 rotatablysupport the second spur gears 69 and 70.

The connection device 60 forms a gear decelerating mechanism by thedrive bevel gear 62, the driven bevel gears 63 and 64 engaged with thedrive bevel gear 62, the first spur gears 67 and 68 coupled with thedriven bevel gears 63 and 64, and the second spur gears 69 and 70engaged with the first spur gears 67 and 68. In this case, since thenumber of teeth of the drive bevel gear 62 is 20, the number of teeth ofthe driven bevel gears 63 and 64 is 40, the number of the first spurgears 67 and 68 is 32, and the number of the second spur gears 69 and 70is 32, a rotation force applied to the drive bevel gear 62 istransmitted to the driven bevel gears 63 and 64 such that the rate isdecelerated and the torque is increased. Accordingly, a relativelyhigher torque is transmitted to the first spur gears 67 and 68 engagedwith the driven bevel gears 63 and 64 and to the second spur gears 69and 70 engaged with the first spur gears 67 and 68.

Next, a connection method for manufacturing the metal linear object 10using the connection device 60 will be described.

First, the main wire 3 is inserted in the through-hole 86 of the othersecond spur gear 70 [[69]] by opening the upper casing 74 of theconnection device 60 or through the concave portion 90 of the lowercasing 73 without opening the upper casing 74, and the end portion 5 ofthe main wire 3 is pulled out through the slit 87 of the other secondspur gear 70 via the spacer 92 by a predetermined length.

Next, from the side opposite to the insertion direction of the main wire3, the branch wire 4 is inserted in the through-hole 86 of the othersecond spur gear 69 [[70]], and the end portion 6 of the branch wire 4is pulled out through the slit 87 of the second spur gear 69 via thespacer 92 by a predetermined length.

Subsequently, the handle 79 of the connection device 60 is rotated byapplying a rotation force thereto. The rotation force is applied by handor a power source not shown in the figure. When the handle 79 starts torotate, since the drive bevel gear 62 is rotated, by this rotationforce, the driven bevel gears 63 and 64 are rotated in the oppositedirections. In this step, the discs 65 and 66 and the first spur gears67 and 68 are rotated in the same directions as those of the drivenbevel gears 63 and 64, respectively, and the second spur gears 69 and 70are rotated in the opposite directions.

Since the second spur gears 69 and 70 are rotated in the oppositedirections, the main wire 3 which passes through from the second spurgear 69 to the other second spur gear 70 and which is disposed at thebottom portions of the slits 87 is screwed by a small twist having along wavelength cycle, and at the same time, the branch wire 4 whichpasses through from the other second spur gear 70 to the second spurgear 69 and is disposed in the through-holes 86 is screwed around themain wire 3 by a large twist having a short wavelength cycle. In thisstep, since a tensile force to the main wire 3 is adjusted by atensile-force application roller not shown in the figure, and the branchwire 4 obtains a tensile force by the resistance to the spacer 92, thetensile load ratio of the main wire 3 to the branch wire 4 is set in therange of 10:3 to 10:6. Accordingly, the main wire 3 and the branch wire4 are pulled to each other toward the connection portion 7 by twisting.

In this step, although the force works to shrink the distance betweenthe second spur gears 69 and 70, since the spacer 92 is providedtherebetween, while the second spur gears 69 and 70 are maintained atpredetermined positions, the twisting is performed.

In addition, since the spacer 92 is disposed at the position in thevicinity of the outside of the main wire 3 and the branch wire 4, whichare hung between the second spur gears 69 and 70, in the diameterdirection, when the twisting is performed, the main wire 3 and thebranch wire 4 are restricted to move outside in the diameter direction.That is, even when the main wire 3 and the branch wire 4 tend to meander(or be decentered) during twisting, they are brought into contact withthe inner circumference surface of the spacer 92, and by this contactresistance, the main wire 3 and the branch wire 4 are stably set alongthe twisting axis (along the rotation shafts of the second spur gears 69and 70). Accordingly, the main wire 3 and the branch wire 4 can betightly twisted with each other. In addition, after the twisting isperformed predetermined times, the handle 79 is stopped so as to stopthe twisting.

Next, as shown in FIG. 7, in the state in which the connection portion 7is formed by twisting the main wire 3 and the branch wire 4, which formthe metal linear object 10, the terminals h1 and h2 of the heatingdevice H used as an electric heating means provided in the connectiondevice 60 are connected to the end portions 5 and 6 of the metal linearobject 10. Subsequently, by tuning on the switch of the heating deviceH, electricity is supplied between the terminals h1 and h2, and by theelectrical resistance of the connection portion 7 itself, the twistedportion is heated to 250 to 500° C. and preferably approximately 400° C.and is maintained for at least 10 seconds or more and preferablyapproximately 20 seconds for annealing. As a result, the diameter shapeforming rate of the connection portion 7 can be made approximately 100%,and the contact resistance of the connection portion can be improved.

Next, by disengaging the upper casing 74 from the lower casing 73through the hinge 75, the upper portion of the lower casing 73 isopened, and an assemble of the spacer 92 and the second spur gears 69and 70 in the lower casing 73 is brought out.

The twisted metal linear object 10 is then brought out through the notchportion 93 of the spacer 92. Subsequently, non-twisted portions of theend portions 5 and 6 extended from the connection portion 7 are cut offby a nipper, a clipper, or the like. As a result, the end portions 5 and6 of the metal linear object 10 are twisted with each other and areplastic-deformed and united together at the connection portion 7, sothat a tight connection state can be obtained.

In addition, without performing annealing after twisting, the connectionportion 7 can be tightly fixed using the low-temperature melting softmetal 8. Accordingly, detwisting of the connection portion 7 can besuppressed, and in addition, the contact resistance thereof can beimproved, thereby obtaining a tight connection state.

As described above, according to this embodiment, the vicinity of theend portion of the branch wire 4 is held in the through-holes 86, thevicinity of the end portion of the main wire 3 is held by the slits 87,the main wire 3 and the branch wire 4 are hung so that the vicinities ofthe end portions thereof are overlapped with each other in the axisdirection, and the second spur gears 69 and 70 are rotated relatively inthe opposite directions around between the through-hole 86 and the slit87 as the rotation center. As a result, between the second rotators 69and 70, when the branch wire 4 is twisted as if screwed around the mainwire 3, the connection can be easily performed, and the main wire 3 andthe branch wire 4 thus twisted together are tightly connected to eachother due to a friction force generated therebetween. In addition, sincethe connection can be performed by simply rotating the second rotators69 and 70 having the through-holes 86 and the slits 87 in the oppositedirections, the connection operation can be easily performed at a lowcost.

In addition, since the branch wire 4 is twisted around the main wire 3in the state in which the main wire 3 and the branch wire 4 which arehung between the pair of the second rotators 69 and 70 are restricted tomove outside in the diameter direction, the main wire 3 and the branchwire 4 can be stably set along the twisting rotation axis, and whilebeing prevented from unstably moving and swinging, the main wire 3 andthe branch wire 4 can be tightly twisted together. In this step, sincethe main wire 3 is disposed close to the rotation center side ascompared to the branch wire 4, the main wire 3 and the branch wire 4 arenot uniformly nor equally overlapped, screwed, and twisted with eachother, and the connection is performed such that the branch wire 4 iswound around the screwed main wire 3. Accordingly, a decrease instrength of the connection portion 7 can be suppressed. That is, themain wire 3 functioning as a central line can be responsible foranti-tensile load and the branch wire 4 functioning as a lateral linecan be responsible for anti-sliding properties.

In addition, since the tensile load ratio of the main wire 3 to thebranch wire 4 can be set in the range of 10:3 to 10:6, the branch wire 4can be more reliably twisted around the screwed main wire 3.

In addition, by supplying electricity from the heating device H betweenthe end portions 5 and 6 of the twisted connection portion 7 of themetal linear object 10, the connection portion 7 placed in theconnection device is heated to a temperature of 250 to 500° C. and ismaintained for 10 seconds or more for annealing. As a result, thediameter shape forming rate of the connection portion 7 is madeapproximately 100% by the simple heating device, so that the contactresistance of the connection portion can be improved.

In addition, by inserting the main wire 3 in the slits 87, the main wire3 can be easily held by the holding portions made of the slits 87. Inaddition, after the main wire 3 and the branch wire 4 are connected toeach other, the metal linear object 10 can be easily removed from theslits 87.

In addition, since the other holding portions are made of thethrough-holes 86, when the branch wire 4 is held by passing through thethrough-holes 86, the outer circumference of the branch wire 4 is heldby the inner circumferences of the through-holes 86 while the main wire3 and the branch wire 4 are twisted together, and the twisting can befurther reliably performed at the connection portion 7.

In addition, at the connection portion 7, the main wire 3 and the branchwire 4 can be tightly twisted with each other by plastic deformation, sothat superior connection state can be obtained. Furthermore, detwistingof the main wire 3 and the branch wire 4 at the connection portion 7 canbe suppressed, and further the strength of the connection portion 7 canbe improved. In addition, without leaving an extra length portion, themain wire 3 and the branch wire 4 can be placed in a connected state.

In addition, in the case in which the metal linear object 10 isintroduced to a path line for a subsequent step as an intermediateproduct, a trouble can be reliably prevented in which the connectionportion 7 is cut off when the cut end portion 5 catches on something andgenerates an excessive load to be applied thereto.

In addition, the main wire 3 is held in the slits 87. Accordingly, themain wire 3 can be easily inserted in the slits 87, and the metal linearobject 10 can be held by the holding portions made of the slits 87.

In addition, since the heating device H for heating only the connectionportion 7 is provided, while being placed in the connection device 60,steps including the annealing can be performed.

In addition, the slits 87 which are the holding portions holding themain wire 3 are opened between teeth provided at the outer circumferencesides of the second spur gears 69 and 70 which are to be engaged withthose of the first spur gears 67 and 68. Accordingly, compared to thecase in which the slit is formed at the tooth position, the teeth of thesecond spur gears 69 and 70 can be reliably engaged with those of thefirst spur gears 67 and 68, and hence a decrease in tooth life and atransmission defect of power from the first spur gears 67 and 68 can besuppressed.

In addition, since the first spur gears 67 and 68 and the driven bevelgears 63 and 64 are concentrically united together, respectively, with aspace interposed therebetween, the length of the spacer 92 for twistingthe branch wire 4 around the main wire 3 can be set large, and inaddition, when the number of the teeth of the first spur gears 67 and 68to be engaged with the second spur gears 69 and 70 is set smaller thatthat of the driven bevel gears 63 and 64, the twisting torque can berelatively increased. In addition, reduction in number of components andsimplification of the structure can be performed, and hence the cost canbe further reduced.

In addition, the connection can be performed by twisting predeterminedlengths of the main wire 3 and the branch wire 4, and in addition, thetwisting can be more uniformly performed.

In addition, since the rotation force is transmitted from the first spurgears 67 and 68 having a smaller outer diameter than that of the discs65 and 66 to the second spur gears 69 and 70, the number of teeth of thefirst spur gears 67 and 68 and that of the second spur gears 69 and 70can be set smaller than that of the driven bevel gears 63 and 64, and byincreasing the transmission torque, the twisting torque can beincreased.

The above connection method has been described by way of example usingthe case in which the main wire 3 and the branch wire 4 are connected toeach other; however, of course, the connection method can also beapplied to the case in which after one metal linear object 10 is warpedto form a circular shape, the end portions 5 and 6 thereof are connectedto each other.

In addition, as the first rotators and the second rotators, instead ofthe first spur gears 67 and 68 and the second spur gears 69 and 70,power transmission means such as spiral gears or pulleys may also beused.

EXAMPLE 1

Next, with reference to FIGS. 8 to 10, Example 1 will be described whichwas performed in order to confirm the operation and effect of the firstembodiment of the connection method and connection device for connectingmetal linear objects, according to the present invention.

As shown in FIG. 8, around a core (strand) 15 formed by twisting 3single element wires 14 of a diameter of 0.17 mm at pitches of 5.0 mm ina S-twisting direction, a sheath layer 17 was formed by twisting 7single element wires 16 of a diameter of 0.20 mm at pitches of 12.0 mmin the same S-twisting direction, as shown in FIG. 9, so that a sheath18 was formed. In addition, a metal cord 20 was investigated which wasformed by winding a wrapping wire 19 of a diameter of 0.15 mm around theouter circumference of the sheath 18 at pitches of 3.50 mm in aZ-twisting direction, which was the opposite direction, as shown in FIG.10.

After the three types of metal linear objects, the core 15, the sheath18, and the wrapping wire 19, forming the metal cord 20 were eachconnected at intervals of approximately 50 m using the above connectiondevice 11, the metal cord 20 was formed. Subsequently, the jointefficiencies (ratio of breaking load of the connection portion to thatof the other portion) of the connection portions of the core 15, thesheath 18, and the wrapping wire 19 were measured and were compared tothe case in which connection was performed by butt welding. Furthermore,the joint efficiencies obtained in the case in which the connectionportions of the core 15, the sheath 18, and the wrapping wire 19 wereeach covered with a low-temperature melting soft metal for tight fixingwere also measured and compared in a manner similar to that describedabove. In addition, the joint efficiencies obtained in the case in whichthe connection portions of the core 15, the sheath 18, and the wrappingwire 19 were annealed at an annealing temperature of 400±20° C.(measured by a contact surface thermometer) for a holding time of 20seconds were also measured and compared in a manner similar to thatdescribed above.

In addition, the connection conditions for the core (strand), thesheath, and the wrapping wire were respectively set as follows.

(1) Core (strand)

Dimension between teeth of second spur gear: 21 mm

Twisting number: 7 rotations

Twisting direction: S direction

Length of connection portion: 19 mm

(2) Sheath

Dimension between teeth of second spur gear: 24 mm

Twisting number: 7 rotations

Twisting direction: S direction

Length of connection portion: 21 mm

(3) Wrapping Wire

Dimension between teeth of second spur gear: 18 mm

Twisting number: 7 rotations

Twisting direction: Z direction

Length of connection portion: 17 mm

The measurement results are shown below.

TABLE I Joint efficiency of metal linear objects by connection type (%)Connection by twisting and Connection by subsequent tight fixing withType of metal linear Connection by butt twisting low-temperature meltingpoint object welding (N = 1) (average of N = 5) soft metal (average of N= 5) (1) Core (strand) 43 49 68 (2) Sheath 41 44 65 (3) Wrapping wire 4573 74

TABLE II Joint efficiency of metal linear objects by connection type (%)Connection by twisting and subsequent annealing Connection by (averageof N = 5) Type of metal linear Connection by butt twisting annealingtemperature: 400° C. object welding (N = 1) (average of N = 5) holdingtime: 20 seconds (1) Core (strand) 43 54 70 (2) Sheath 41 49 69 (3)Wrapping wire 45 74 73

Furthermore, with respect to the joint efficiency at an annealingtemperature of 400° C., the joint efficiencies at an annealingtemperature of 200° C. and 600° C. were measure and were compared in amanner similar to that described above. The measurement results areshown below.

TABLE III Joint efficiency by annealing temperature Type of metal linearafter connection of metal linear objects (%) object 20 ± 10° C. 400 ±20° C. 600 ± 30° C. (1) Core (strand) 55 70 53 (2) Sheath 51 69 55 (3)Wrapping wire 71 73 50

As described above, it was confirmed that by the connection method andconnection device for metal linear objects, according to the presentinvention, in the individual metal linear objects, the joint efficiencycould be improved, and tight connection could be performed. Inparticular, it was found that when tight fixing was performed with thelow-temperature melting soft metal after the twisting was performed, asuperior joint efficiency could be obtained. In addition, it was alsofound that annealing at a temperature of approximately 400° C. was moreeffective.

EXAMPLE 2

Next, with reference to FIGS. 8 to 10, Example 2 (change in connectionportion length) will be described which was performed in order toconfirm the operation and effect of the second embodiment of theconnection method and connection device for connecting metal linearobjects, according to the present invention.

As shown in FIGS. 8 to 10, the core (stand) 15, the sheath 18, and thewrapping wire 19 are the same as those described in Example 1, andinvestigation was performed in a manner similar to that described above.

Three types of metal linear objects, the core 15, the sheath 18, and thewrapping wire 19, forming the metal cord 20 were each connected at 5places at intervals of approximately 50 m using the connection device60, and the metal cord 20 was then formed. The joint efficienciessimilar to those of the above Example 1 were measured and compared. Inaddition, the joint efficiencies at an annealing temperature of 200° C.and 600° C. were measured and compared with the case of an annealingtemperature of 400° C. in a manner similar to that described above.

In addition, the connection conditions for the core (strand), thesheath, and the wrapping wire were respectively set as follows.

(1) Core (strand)

Dimension between teeth of second spur gear: 34 mm

Twisting number: 11 rotations

Twisting direction: S direction

Length of connection portion: 31 mm

(2) Sheath

Dimension between teeth of second spur gear: 39 mm

Twisting number: 11 rotations

Twisting direction: S direction

Length of connection portion: 35 mm

(3) Wrapping Wire

Dimension between teeth of second spur gear: 29 mm

Twisting number: 10 rotations

Twisting direction: Z direction

Length of connection portion: 28 mm

The measurement results are shown below.

TABLE IV Joint efficiency of metal linear objects by connection type (%)Connection by twisting and Connection by subsequent tight fixing withType of metal linear Connection by butt twisting low-temperature meltingpoint object welding (N = 1) (average of N = 5) soft metal (average of N= 5) (1) Core (strand) 43 54 70 (2) Sheath 41 49 68 (3) Wrapping wire 4574 75

As shown above, it was confirmed that by the connection method andconnection device for metal linear objects, according to the presentinvention, by using the main wire 3 and the branch wire 4, the jointefficiency could be improved, and tight connection could be performed.In particular, it was found that when tight fixing was performed withthe low-temperature melting soft metal after the twisting was performed,a superior joint efficiency could be obtained. In addition, it was alsofound that annealing at a temperature of approximately 400° C. was moreeffective. In addition, since the measurement results of the annealingin this Example 2 were the same as the joint efficiencies shown inTables II and III, the results were not shown.

Although the present invention has been described in detail withreference to the particular embodiments, it is naturally understood by aperson skilled in the art that various modifications and changes may bemade without departing from the sprit and scope of the presentinvention.

This application claims the benefit of Japanese Application No.2007-002797 filed Jan. 10, 2007, No. 2007-050572 filed Feb. 28, 2007,No. 2007-197200 filed Jul. 30, 2007, No. 2007-331583 filed Dec. 25,2007, No. 2007-340955 filed Dec. 28, 2007, No. 2007-340956 filed Dec.28, 2007, No. 2008-001565 filed Jan. 8, 2008, and No. 2008-001566 filedJan. 8, 2008, which are hereby incorporated by reference herein in theirentirety.

INDUSTRIAL APPLICABILITY

As described above, the connection method and connection device forconnecting metal linear objects, according to the present invention, canbe applied, for example, to a connection method and connection devicefor connecting steel cords.

1. A connection method for connecting metal linear objects facing eachother, comprising the steps of: disposing a pair of rotators with aspace interposed therebetween, each rotator including a pair of holdingportions which are provided with a space interposed therebetween andwhich are able to hold the metal linear objects; holding the vicinitiesof end portions of the metal linear objects at the holding portions ofthe rotators to hang the metal linear objects therebetween so that thevicinities of the end portions of the metal linear objects areoverlapped with each other in an axis direction; and rotating therotators relatively in the opposite directions around between the pairof holding portions as a rotation center, whereby the metal linearobjects are twisted with each other between the rotators to performconnection.
 2. The connection method for connecting metal linearobjects, according to claim 1, wherein in the state in which the metallinear objects which are hung between the pair of rotators arerestricted to move outside in the diameter direction, the rotators arerotated.
 3. A connection method for connecting metal linear objectsfacing each other, comprising the steps of: disposing a pair of rotatorswith a space interposed therebetween, each rotator including a pair ofholding portions which are provided with a space interposed therebetweenand which are able to hold the metal linear objects; holding thevicinities of end portions of the metal linear objects, which are a mainwire and a branch wire, at the holding portions of the rotators to hangthe metal linear objects therebetween so that one metal linear objectused as the main wire is disposed close to a rotation center side ascompared to the other metal linear object used as the branch wire, andso that the vicinities of the end portions are overlapped with eachother in an axis direction; and in the state in which the metal linearobjects which are hung between the pair of rotators are restricted tomove outside in the diameter direction, rotating the rotators relativelyin the opposite directions around between the pair of holding portionsas the rotation center, whereby the metal linear objects are twistedwith each other between the rotators to perform connection.
 4. Theconnection method for connecting metal linear objects, according toclaim 3, wherein a tensile load ratio of the main wire to the branchwire is set in the range from 10:3 to 10:6.
 5. The connection method forconnecting metal linear objects, according to claim 1, wherein as theholding portions of the rotators, slits are formed, each of which isopened at the outer circumference side of each rotator and is extendedto the vicinity of the rotation center thereof, and by inserting themetal linear objects in the slits, the metal linear objects are held inthe slits.
 6. The connection method for connecting metal linear objects,according to claim 5, wherein the rotators have the slits as one type ofholding portion and, as the other type of holding portion, through-holesthrough which the metal linear objects are allowed to pass.
 7. Theconnection method for connecting metal linear objects, according toclaim 1, wherein the metal linear objects comprise a material whichgenerates plastic deformation.
 8. The connection method for connectingmetal linear objects, according to claim 1, wherein the two end portionsof the two linear objects are applied with tensile resistance duringtwisting so as to perform uniform screwing.
 9. The connection method forconnecting metal linear objects, according to claim 1, wherein when themetal linear objects are element wires, a plurality of which issubsequently twisted together into a strand wire, the twisting directionwhile the end portions are connected to each other is set to coincidewith the twisting direction when a strand wire is formed.
 10. Theconnection method for connecting metal linear objects, according toclaim 1, wherein when the metal linear objects are wires formed bytwisting a plurality of element wires, the twisting direction while theend portions are connected to each other is set to coincide with thetwisting direction of the element wires.
 11. The connection method forconnecting metal linear objects, according to claim 1, wherein after themetal linear objects are connected to each other by twisting, at leastone extra length portion of the end portions which are not twistedtogether is removed by cutting.
 12. The connection method for connectingmetal linear objects, according to claim 11, wherein at least one of theend portions which are not twisted together is bent in the directionopposite to an introduction direction, and an extra length portion iscut off so as to leave a part thereof as a bent formation part.
 13. Theconnection method for connecting metal linear objects, according toclaim 1, wherein after the metal linear objects are twisted together,the twisted portion is annealed at 250 to 500° C. for 10 seconds ormore.
 14. The connection method for connecting metal linear objects,according to claim 1, wherein at a connection portion formed by twistingthe metal linear objects together, the metal linear objects are tightlyfixed to each other by a low-temperature melting soft metal.
 15. Theconnection method for connecting metal linear objects, according toclaim 1, wherein after the twisting is performed, a connection portionis plastic deformed by applying a compression force thereto.
 16. Aconnection device for connecting metal linear objects facing each other,comprising: a pair of second rotators which are rotatably providedaround the same axis center, each having a pair of holding portionsbeing capable of holding the metal linear objects and provided aroundthe axis center; a pair of first rotators engageable with teeth formedalong the peripheries of the second rotators; driven bevel gears to berotated with the respective first rotators; and a drive bevel gearengaged with the two driven bevel gears, wherein by rotation of thedrive bevel gear, the driven bevel gears are rotated in the oppositedirections, the rotations thereof are transmitted to the second rotatorsthrough the first rotators, and the second rotators are rotated in theopposite directions, whereby end portions of the metal linear objectsheld by the holding portions are twisted between the second rotators.17. The connection device for connecting metal linear objects, accordingto claim 16, further comprising a linear object restriction member forrestricting the metal linear objects which are hung between the pair ofsecond rotators to move outside in the diameter direction, wherein theend portions of the metal linear objects are twisted together whilebeing restricted to move outside in the diameter direction between thesecond rotators by the linear object restriction member.
 18. Aconnection device for connecting metal linear objects facing each other,comprising: a drive bevel gear to which a rotation force is applied; apair of driven bevel gears which are intersected with the drive bevelgear and are applied with the rotation force; a pair of discs integrallybonded to the respective driven bevel gears; a pair of first rotators tobe concentrically and integrally rotated with the respective discs; apair of second rotators which are engaged with the respective firstrotators, which are rotatably provided around the same axis center, andeach of which have a pair of holding portions provided around the axiscenter and being capable of holding the metal linear objects; and alinear object restriction member for restricting the metal linearobjects which are hung between the pair of second rotators to moveoutside in the diameter direction, wherein by rotation of the drivebevel gear, the driven bevel gears are rotated in the oppositedirections, the rotations thereof are transmitted to the second rotatorsthrough the first rotators, and the second rotators are rotated in theopposite directions, whereby end portions of the metal linear objectsare twisted together while being restricted by the linear objectrestriction member to move outside in the diameter direction between thesecond rotators.
 19. The connection device for connecting metal linearobjects, according to claim 16, further comprising an electric heatingmeans which heats only a connection portion after the end portions ofthe metal linear objects are twisted together.
 20. The connection devicefor connecting metal linear objects, according to claim 16, wherein asthe holding portions, slits are formed, each of which is opened at theouter circumference side of each second rotator and is extended to thevicinity of the axis center, and by inserting the metal linear objectsin the slits, the metal linear objects are held in the slits.
 21. Theconnection device for connecting metal linear objects, according toclaim 20, wherein the slits are each opened between teeth provided atthe outer circumference side of each second rotator which are to beengaged with those of the corresponding first rotator.
 22. Theconnection device for connecting metal linear objects, according toclaim 16, wherein the first rotators are united with the respectivedriven bevel gears.
 23. The connection device for connecting metallinear objects, according to claim 22, wherein the first rotators areconcentrically united with the respective driven bevel gears with aspace interposed therebetween.
 24. The connection device for connectingmetal linear objects, according to claim 16, wherein the second rotatorsare engaged with pairs of idle rotators located at the side opposite tothe first rotators, and by the idle rotators, the second rotators aresupported at the side opposite to the first rotators.
 25. The connectiondevice for connecting metal linear objects, according to claim 16,further comprising a spacer having a predetermined length dimensionprovided between the second rotators.
 26. The connection device forconnecting metal linear objects, according to claim 25, wherein thespacer is the linear object restriction member.
 27. The connectiondevice for connecting metal linear objects, according to claim 16,wherein the number of teeth of each first rotator is smaller than thenumber of teeth of each driven bevel gear.